A 26-year-old woman presented with a slow-growing right breast lump. Excision biopsy of the lump showed invasive ductal carcinoma with adjacent ductal carcinoma in situ (DCIS). Preoperative imaging was performed to assess the extent of disease. Magnetic resonance (MR) imaging of the breasts showed an area of clustered ring enhancement deep to the biopsy site, which was representative of residual DCIS. DCIS is a common noninvasive malignancy that manifests as a primary breast tumour or in association with other lesions. The radiological features of DCIS are discussed herein, with special attention to the clustered ring enhancement pattern on MR imaging.
